SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '3bdee0b6593dd0dabcf77b5a3c91d0cdbe106438bc649f97d719192025f67df2' 
  AND token = 'DhmlszQ/93AW81YL8HpTsO5hFmbjAbkIMW8PCoa17WE=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00031

JSON explain

{
  "query_block": {
    "select_id": 1,
    "message": "no matching row in const table"
  }
}